Can swishing hydrogen peroxide in your mouth, spitting it out and then brushing your teeth routinely, whiten your teeth?

Yes, but dangerous..: This technique can slightly whiten your teeth, but my concern is that use of high concentration hydrogen peroxide regularly around your mouth as a rinse can inadvertently kill off good bacteria. This can lead to fungal infections that could require treatment... Talk to your dentist about safer, simple alternatives to whiten your teeth...

To a degree : Most of the whitening gels or whitening liquids are formed from carbamide peroxide with various concentrations. This material reacts with water to form hydrogen peroxide. 15% carbamide peroxide liquid is equal to 5% hydrogen peroxide. The hydrogen peroxide liquid sold over the counter is usually 3% . So it is possible to a certain degree that using little bit of it swish swashing could help.

No: Over the counter hydrogen peroxide does not whiten teeth.

H2O2 tooth whitening: It can, but there are precautions you need to take. Exposure time for one. You don't want the peroxide to burn or slough you gum tissue, this could be very uncomfortable. It is not ideal but the following link can give you a technique that can be safe if followed. http://www.wikihow.com/whiten-teeth-with-hydrogen-peroxide cheers.